# SCM Power Analysis: Minimum Detectable Effects

*Given pre-treatment fit quality, what magnitude of effect would be detectable at the 10% level?*

| Country | Pre-RMSPE | Post-RMSPE | Ratio | Avg Gap | MDE (2×pre) | MDE (3×pre) | N pre | N post |
|:---|---:|---:|---:|---:|---:|---:|---:|---:|
| MNG | 2.88 | 16.22 | 5.63 | -- | 5.76 | 8.64 | -- | -- |
| RUS | 17.93 | 10.57 | 0.59 | -- | 35.86 | 53.79 | -- | -- |
| AZE | 10.16 | 29.72 | 2.92 | -- | 20.32 | 30.48 | -- | -- |
| BLR | 2.82 | 6.00 | 2.13 | -- | 5.63 | 8.45 | -- | -- |
| TJK | 16.58 | 7.96 | 0.48 | -- | 33.17 | 49.75 | -- | -- |
| GEO | 2.65 | 3.18 | 1.20 | -- | 5.31 | 7.96 | -- | -- |
| KGZ | 8.73 | 18.21 | 2.09 | -- | 17.45 | 26.18 | -- | -- |

*MDE = minimum detectable effect as multiple of pre-treatment RMSPE.*
*To achieve p<0.10 in permutation inference with ~130 donors, the post/pre RMSPE ratio must rank in the top ~13 units.*
*A ratio of 2-3× pre-RMSPE is typically needed; effects smaller than pre-RMSPE are undetectable.*
*Countries with pre-RMSPE > 5 pp have poor synthetic fit and are uninformative.*